Simplify the following expression: $r = \dfrac{4}{4t - 5} \div \dfrac{6}{4t}$
Dividing by an expression is the same as multiplying by its inverse. $r = \dfrac{4}{4t - 5} \times \dfrac{4t}{6}$ When multiplying fractions, we multiply the numerators and the denominators. $r = \dfrac{ 4 \times 4t } { (4t - 5) \times 6}$ $r = \dfrac{16t}{24t - 30}$ Simplify: $r = \dfrac{8t}{12t - 15}$